 /*******************************************************************************
  * Copyright (c) 2000, 2004 IBM Corporation and others.
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License v1.0
  * which accompanies this distribution, and is available at
  * http://www.eclipse.org/legal/epl-v10.html
  *
  * Contributors:
  * IBM Corporation - initial API and implementation
  *******************************************************************************/
 package org.eclipse.test.internal.performance.eval;

 import org.eclipse.test.internal.performance.PerformanceTestPlugin;
 import org.eclipse.test.internal.performance.data.Dim;

 /**
  * @since 3.1
  */
 public class RelativeBandChecker extends AssertChecker {

     private final double fLowerBand;
     private final double fUpperBand;

     public RelativeBandChecker(Dim dimension, double lowerBand, double upperBand) {
         super(dimension);
         fLowerBand= lowerBand;
         fUpperBand= upperBand;
     }

     public boolean test(StatisticsSession reference, StatisticsSession measured, StringBuffer message) {
         Dim dimension= getDimension();
         
         if (!measured.contains(dimension)) {
             PerformanceTestPlugin.logWarning("collected data provides no dimension '"+dimension.getName()+'\''); //$NON-NLS-1$ //$NON-NLS-2$
 return true;
         }
         if (!reference.contains(dimension)) {
             PerformanceTestPlugin.logWarning("reference data provides no dimension '"+dimension.getName()+'\''); //$NON-NLS-1$ //$NON-NLS-2$
 return true;
         }
         
         double actual= measured.getAverage(dimension);
         double test= reference.getAverage(dimension);
         
         if (test < 0.001 && test > -0.001) {
             // we don't fail for reference value of zero
 PerformanceTestPlugin.logWarning("ref value for '"+dimension.getName()+"' is too small"); //$NON-NLS-1$ //$NON-NLS-2$
 return true;
         }
         if (actual < 0) {
             // we don't fail for negative values
 PerformanceTestPlugin.logWarning("actual value for '"+dimension.getName()+"' is negative"); //$NON-NLS-1$ //$NON-NLS-2$
 return true;
         }
         
         if (actual > fUpperBand * test || actual < fLowerBand * test) {
             message.append('\n' + dimension.getName() + ": " + dimension.getDisplayValue(actual) + " is not within [" + Math.round(fLowerBand * 100)+ "%, " + Math.round(fUpperBand * 100) + "%] of " + dimension.getDisplayValue(test)); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$ //$NON-NLS-4$
 return false;
         }
         return true;
     }
 }

